The rear wheel of a bicycle is typically attached to the frame by dropouts that removably receive the rear wheel. These dropouts are typically fabricated with the frame as a unitary or one-piece body. If the dropouts are formed of a material different than the frame, such as when a frame is fabricated of carbon fiber or the like, the dropouts are permanently affixed to the frame such as by being incorporated into the structure during manufacture, welding, adhesive or the like.
Bicycles can be generally categorized into two main groups for the purpose of this disclosure, those with multiple gears and those with a single gear. These two categories of bicycles require specific structures to accommodate the different mechanical structures found in each. Specifically, in a single gear bicycle, the chain is maintained at a specific tension. With a permanent dropout, there is no problem, since the dropout is immovable and a chain of the appropriate length for the desired tension can be employed. However, for multiple gear bicycles, the tension on a chain having the same length can vary, depending on the gear employed. Thus, multiple gear bicycles employ a chain tensioner or derailleur.
While each of these works perfectly adequately for its intended purpose, the frames of each cannot be used interchangeably since the requirements of each are different. In other words, the frame of a single gear bicycle cannot be used as a multiple gear bicycle and visa versa. This problem has not been adequately addressed in the bicycle industry.
It would be highly advantageous, therefore, to remedy the foregoing and other deficiencies inherent in the prior art.
An object of the present invention is to provide a frame which can be used as a multiple gear bicycle or a single gear bicycle.
Another object of the present invention is to provide a bicycle frame having interchangeable dropout sets for single gear bicycles or multiple gear bicycles.